One Night
by JullietteO'Hara
Summary: One night. That was it. One night four years ago. Four years, three months and twelve days, if he was being specific and despite his best efforts he couldn't erase the memory of her. Little did he know that night resulted in a baby boy with a face like his mother and eyes like his father. Parent!Lock. Sherlolly. AU.
1. Chapter 1

One night. That was it. One night four years ago. Four years, three months and twelve days, if he was being specific and he could still feel the wind on his face as he threw himself off the roof of St. Barts. But it wasn't the memory of wind that kept him sane while he was away protecting the ones he loved the most.

It was her.

He'd gone to her, broken and afraid, a fraud, and she, with her unfailing faith did not doubt or interrogate. She'd only wanted to know one thing.

"What do you need?"

And in that moment he was honest with himself, more honest than he'd been in years. It wasn't the smell of chemicals that made his heart rate increase when he entered the lab, an excuse he told himself more than he cared to admit. Nor was it the excitement of catching criminals, another defense he employed often. It was the big brown eyes that would glance at him over the lenses of a microscope, the furrowed brow of a woman who struggled with her surgical gloves, the bottom lip captured between white teeth as it was chewed in concentration. He only needed one thing. He only ever needed one thing.

"You."

It was those thoughts that propelled a dead man to the doorstep of Molly Hooper. She was surprised, as he'd anticipated, considering that after their plan was a success the two parted ways, an unspoken goodbye hanging in the air between them. But that wasn't enough for him and if, when she opened the door, her red-rimmed eyes were any indication, it wasn't enough for her either.

For four years, three months, and twelve days it was the memory of their night that sustained him through cold nights in cramped spaces as he waited without any leads on Moriarty's criminal empire. The feeling of her mouth against his as she pulled him through the entryway, her nails raking through his dark curls, gently scratching against his scalp, made those dreary nights bearable.

When he'd woken up the next morning the sun was nowhere to be seen and streaks of moonlight peaked through the drawn curtains of Molly's bedroom, illuminating her sleeping form. She was curled next to him, soft puffs of breath beating against his bare chest, her eyelashes fluttering against her cheek as she dreamed. He stared for a while, memorizing every inch of her (as though he hadn't already) and stored her image in his mind palace, although even if he hadn't he knew he would never be able to forget the way they…

When he stayed as long as he knew he possibly could, he slowly slid out of bed, careful not to stir her. He picked up his clothes that had been haphazardly thrown about, chuckling softly at the way she'd laughed at him when he, for the life of him, could not get her "blasted contraption" off. He stopped when he saw her stirring. Her eyes fluttered open, still glossy with sleep, but as she looked at him, she knew. He leaned over the bed and pressed a chaste kiss to her lips.

"I will be back, Molly," he whispered in the darkness.

"I know you will be." Her unyielding faith, once again, caused the corners of his mouth to turn up in a smile that didn't quite reach his eyes.

"Goodbye, Sherlock Holmes."

"Goodbye, Molly Hooper."

By the time he reached the door to her bedroom, she had already fallen back to sleep.

As a dead man he exited her flat and walked out into the street, unrecognizable. A part of him, the small part in the deepest, darkest corner of his heart, the part that held the sentiment he so desperately tried to conceal, wished he could stay, wished the two of them could have woken up together, been domestic as they shared shy smiles over coffee and simply enjoyed each other's company. He wanted that more than he'd ever care to admit but instead of waking up next to the woman he loves, he was walking away from her, the moon still high in the sky.

But now…now he is back.


	2. Chapter 2

**_A/N: I plan on updating this fic on a regular schedule, every Wednesday and possibly Sunday, and I promise it will get interesting. These first few chapters are mainly exposition (which I'm not very good at writing). Reviews are always lovely._**

* * *

He went to his brother first. Well…technically his brother came to him.

The rhythmic echo of water droplets against the stone floor sounded in the ears of Mycroft Holmes as he sat in the shadows. It had taken British intelligence weeks to find out exactly where the leads on Moriarty's criminal empire led Sherlock but they were eventually successful. Mycroft found his brother battered and bloody, chained to a wall in a small shack in Serbia, unrecognizable with curly hair reaching his shoulders, matted to his forehead with sweat, and an unruly beard catching the blood that poured from his busted lip. The water leaking through the ceiling was soon muffled by the sound of fists pounding against flesh and the rattling of chains.

Groans of agony were replaced with mumbled deductions as Sherlock studied his interrogator. The guard, obviously shocked at the accuracy of Sherlock's comments, raced from the room, the steel door slamming behind him. Silence followed. Mycroft, rising from his seat approached the brother he had not seen in years.

"Now listen to me," he whispered into his brother's ear. "There is a case in London that requires your assistance. A massive attack is imminent. Sorry, but the holiday is over, brother dear. Back to Baker Street, Sherlock Holmes. "

* * *

"A small thank you wouldn't go amiss," Mycroft said as he sat behind his desk, organizing all of the papers he'd just finished showing the consulting detective regarding his new assignment.

"What for?" Sherlock asked as the remnants of his time away fell into the bin beneath his head and the snip of scissors sounded in his ears.

"For wading in."

"Wading in? You sat there and watched me being beaten to a pulp."

"I got you out."

"No I got me out. Why didn't you intervene sooner?"

"I couldn't risk giving myself away."

"You were enjoying it."

"Nonsense." A heavy silence followed. "You realize there have been many changes since your departure Sherlock," Mycroft said changing the subject. "It will be difficult for them all to readjust to your return. "

"I am well aware things change, Mycroft," Sherlock mumbled, annoyed.

"I am not entirely sure if you are prepared for these changes Sherlock…They are quite extreme."

"Stop being so dramatic. I am aware things will be different. People age. They move on. Now get on with it. How is John?" Sherlock stood up, turning to his brother, his face freshly shaved and his hair returned to its usual curl. He removed the robe that he was wearing and held his arm out. Mycroft's assistant who had cut his hair passed him a white button down that he put on immediately.

"Married."

Sherlock's fingers fumbled with the button he was working on as his face visibly paled.

"And with a one year old daughter. Elizabeth…Lizzie. She's quite adorable. Had you been around, I'm sure they'd have made you the godfather."

"Is that so?" Sherlock feigned nonchalance but Mycroft could detect a tinge of pain in his voice.

"Mary is his wife's name. You will like her. She is quite intelligent."

"Are they—"

"No. They do not reside at 221B. Although Mrs. Hudson refuses to let out the flat. You should find it exactly as you left it.

"Good," was all Sherlock could manage.

"If you go now you should be able to catch them at the park. You know, the one walking distance from the morgue you used to frequent. St Bartholomew's."

"I am aware of the park."

"Mary brings the child to the park every afternoon and John usually joins them on his lunch break. That is unless he has a particularly demanding patient.

"Alright." Sherlock nodded. Mycroft could tell the news upset him like he'd anticipated. While John and his little brother had never been anywhere close to being romantically involved, they had been the very best of friends and it was clear by his reaction, Sherlock had not anticipated John to move on from their friendship in such a drastic fashion.

"I'll just be going then," Sherlock stated after a long moment of silence. The consulting detective moved to the door.

"And Sherlock," Sherlock turned around. "Be careful."

The younger Holmes brother nodded and walked out of the office.


	3. Chapter 3

_**A/N: Okay, this isn't relevant to this chapter but in the last chapter I changed Lizzie's age to around one instead of two. It just works better for later in the story.**_

* * *

Sherlock sat underneath a tree in the park Mycroft had directed him to, the bark poking through the thin material of his shirt while the remnants of the previous evening's rain seeped through the disheveled trousers of his homeless costume. The tin can in his hand jangled as the few coins inside beat against the metal whenever someone walked by. His eyes scanned the expanse of grass laid out before him while his ears blocked out the screeches of nearby children as they played. Seeing as how Mycroft did not give him a very detailed description of Mary, Sherlock looked out for John amongst the sea of children, until a mop of curly brown hair blocked his line of sight.

A boy stood before Sherlock eyeing him quizzically.

"You don't need money," the boy stated matter-of-factly.

When Sherlock's gaze turned to the boy and he was met with a pair of icy blue eyes that paralleled his own.

"And why would you say that?" Sherlock asked. He'd smeared dirt on his face and the clothes were undoubtedly authentic if their smell was any indication. The small child gave him another once over before responding.

"Your teeth are too white!" said the boy excitedly. "And your nails are too clean." Ignoring the overwhelming feeling of familiarity, Sherlock figured the small boy simply reminded him of himself when he was that age, Sherlock furrowed his brow as he deduced the child in front of him.

"You're quite perceptive for a five year old."

"Three."

Sherlock looked surprised. His limited experience with children hindered his deduction abilities for anyone below the age of about 10, but even then, Sherlock could tell that the child before him was much smarter than the average three year old.

"Right."

Taking a seat in the dirt, the boy leaned his back against the tree, finding a position identical to Sherlock's.

"Why…Why are you here?" the child asked, staring at Sherlock with wide eyes.

"Well, if you must know I am looking for someone."

"Who?"

"My friend."

"What's his name?"

"John."

"Is his homeless?"

"No."

"Then…then why do you…then why do you look homeless?"

"To surprise him."

"Why?"

"Because I haven't seen him in a long time."

"Oh."

There was a long pause as Sherlock continued to survey the park. Still no sign of John.

"Why were you away?"

"You ask a lot of questions."

"Oh. Sorry." The boy looked down sullen.

"Don't apologize. It is good to learn when your young so you don't grow up to be an idiot." Sherlock felt the corners of his mouth turn up when the boy let out a hearty laugh.

"You didn't answer my question," the child stated when his laughter finally died down.

"I was working."

"For how long?"

"Four years."

"Wow."

"Mm-hmm."

"Did you miss him?"

"Who?"

"John."

"Oh." Sherlock thought for a moment. "Yes. Yes, I did miss him."

"Do you have any other friends?"

"Very few. I am not an easy man to get along with."

"I don't think it's that hard," the boy said. Sherlock, against his will, found himself smiling.

"Well, you're the first."

"What job do you have?"

"I am the world's only consulting detective."

"What do you do as a det…detect—"

"Detective."

"That."

"I solve crimes."

"How?"

"Do you see that woman over there?" Sherlock asked pointing to a woman sitting on a bench directly across from the pair, talking on her mobile. They boy nodded. "She is a painter. Married but she is having an affair with the man she is meeting here today." Sherlock glanced down to find the child staring at him in awe.

"How do you know that?" the boy asked, shaking excitedly.

"See the way she is holding her mobile? There is a callus on the inside of her thumb from holding a palette. She is not wearing a wedding ring but there is a tan line where it should be, meaning she's taken it off recently. I suspect it is in the bag sitting next to her.

"Woah."

Sherlock, fueled by the boys' apparent fascination, found himself continuing.

"And that man over there," Sherlock gestured to the gentleman passing in front of them. "He is a—"

"Doctor!"

"Very good. How could you tell?"

"Pager on his trousers. Me mum's got one." Sherlock nodded his approval.

"You really are quite perceptive."

"Um…I don't know what that means."

"Smart," Sherlock said simply. The boy smiled. "Where are your parents anway?"

"Me mum's at work."

"Your father?"

"I don't got one."

"I see."

"What's your name?" The boy asked standing up so he was eye level with Sherlock.

"Sherlock. Sherlock Holmes. But don't tell anyone you've seen me. I'm not supposed to be back quite yet."

"Okay. My name is S—"

"Scott!" A young woman shrieking in the distance drew the attention of both boys. Not older than twenty-five, the woman came bustling over to where the pair had grown comfortable. Flustered and out of breath she scooped up Scott in her arms, peppering kisses over his face. Scott, obliviously disgusted, squirmed out of her grasp. When the woman Sherlock deduced to be Scott's baby sitter put the boy down, she kneeled so that they would be eye level.

"Now Scott, what did I tell you about running off. You could have been hurt or worse." Scott became fixated on his shoes as he was reprimanded, gently kicking a small pebble. He muttered something incomprehensible. The sitter smiled and standing up brushed the dirt from her trousers. Taking Scott's hand in her own, she turned her attention to Sherlock for the first time since she appeared.

"Oh, sir I'm so sorry." She reached into the large bag she had over her shoulder and pulled out a few pounds, tossing them into the tin can that lay forgotten beside Sherlock. "There you go."

"But he doesn't—" Scott started but one stern look from the sitter silenced him. The boys gaze turned to Sherlock who offered him a conspiratorial wink. Scott replied with a wide grin as he was pulled away. Sherlock watched as the boy trailed behind his sitter until a familiar head caught his attention.

John Watson, accompanied by a pretty blonde whom Sherlock believed to be Mary, was pushing a stroller in his direction, a hideous mass of hair adorning his upper lip.


	4. Chapter 4

_**A/N: Reviews are always lovely.**_

If Sherlock's bloody nose was any indication, John Watson did not take Sherlock's reappearance well. Completely oblivious at first, it took Sherlock multiple attempts to even capture John's attention. Too preoccupied with his wife and daughter, Sherlock's tin can was practically underneath John's nose, the coins inside jingling fiercely, before he looked up and was met with a pair of blue eyes he hadn't seen in years. Shock immediately overcame John Watson. And that shock was replaced with confusion and ultimately resulted in utter and inconsolable rage. That, in combination with Sherlock's teasing remarks about his facial hair, led John Watson's fist directly into Sherlock's face.

A worried wife, a crying baby, and a hoard of concerned spectators, led the four to a location a bit more private.

"How? How could you do it?" John was fuming as he paced up and down the linoleum tiles of the small diner the four had ducked into. Sherlock was leaning against the counter, a handkerchief to his nose in an attempt to lessen the bleeding, with Mary to his right, attempting to comfort the wriggling baby in her arms; they both let John pace, neither saying a word.

"You let me grieve," John exhaled, his fists clenched at his sides. "Four years…Four bloody years. Well for goodness sake, say something!"

"Are you really going to keep that," Sherlock laughed, motioning towards the mustache on John's upper lip.

"Mary likes it."

"No she doesn't."

John looked at Mary with pleading eyes but was only met with a shy smile in return.

"You too? Oh! Why didn't you say something?"

"It's not _awful_ , John," Mary chuckled.

"Yes it is," Sherlock stated.

John's hands were very nearly around Sherlock's neck when the soft coos of his daughter reached his ears. His hands dropped to his sides and he sighed heavily, reaching for his little girl instead, mumbling words of fatherly assurance as he rocked her in his arms, offering his undivided attention while she babbled nonsensically.

"I do believe belated congratulations are in order," Sherlock said, finally. "On both your union and your ability to reproduce. She has your eyes, John."

"Thank you, Sherlock," John replied quietly after a long and heavy silence.

"I hate to be the one to cut this lovely reunion short," Mary started, "but, John, look at the time. Don't you have a patient at one?"

"You're right, yes. Goodbye, Lizzie," John whispered, brushing his lips over his daughters soft blonde curls, before passing her to her mother. The baby girl smiled and waved at her father who contorted his own face into an expression Sherlock deemed utterly ridiculous despite its success in making Lizzie laugh. Lizzie continued to wave and John waved back at his daughter playfully. Sherlock felt the corners of his mouth turn up at the exchange but he quickly schooled his features, although not before receiving a quirked eyebrow from Mary. Sherlock narrowed his eyes at her but Mary's knowing smile only widened.

"Okay, I'd better be off," John said before leaning in to kiss his wife goodbye. He turned to Sherlock, his mouth set in a firm line. Sherlock stood there awkwardly, unsure of what to expect from the man in front of him. John, before he was fully aware of what he was doing, wrapped his arms around Sherlock in a tight hug. Sherlock's eyes widened but before he could attempt to return the display of affection, John had let go and was on his was out the door.

"He's glad you know," Mary said once the bell over the door had stopped jingling. "Glad you're back. He might not be able to admit it but he is."

"John looks like he had fared rather well without me."

"Your death was hard on him, Sherlock. Really, really hard. You'd best give him some time."

"He seems…softer, and I am not referring to the twelve pounds he has gained since my departure. A side effect from marital bliss, I presume." Sherlock, hesitant at first, ran a gentle hand over Elizabeth's head. "It appears to me that your introduction in John's life has resulted in significant improvements."

"Give it a little while, Sherlock. We'll be good for you too," Mary offered cheekily. Sherlock laughed.

"I don't doubt it."

"Now if you'll excuse us, it's time for this little one's nap."

Sherlock nodded understandingly and watched as Mary and Lizzie left the diner.


	5. Chapter 5

**_A/N: Sorry this took so long. Basically this chapter sucks but it's kind of the most important one in the whole piece and I really wanted to post another chapter so here it is. I'm hoping that the next chapter will be less painful to write.  
_**

* * *

To 221B Baker Street Sherlock returned later that evening greeting, a rather startled, Mrs. Hudson. The not-his-housekeeper did not take his return lightly. When he'd insured the landlady had not injured herself when she dropped the tray she'd been carrying, Sherlock got down to business. The scent of familiarity hung in the air as he got reacquainted with flat he hadn't seen in years, although Mycroft was right, everything was exactly how he left it before that fateful day at Bart's. The file Mycroft had given Sherlock was splayed out on the wall, pictures of potential suspects connected to notes by a mash of multicolored string.

The consulting detective paced around the room, his eyes fixated on the information in front of him, but his mind unable to make sense of it. But then again, Sherlock's mind wasn't really all there. No. His thoughts were back at Bart's with a pair of big brown eyes in a white lab coat. Sighing heavily, Sherlock pounded his fist against the wall before collapsing on the couch. He steepled his hands beneath his chin, the tips of his middle fingers barely brushing the edge of his nose, and attempted to sort his mind palace. But down every hallway he'd turn, mind-Sherlock would catch a glimpse of a white lab coat turning a corner or a soft giggle echoing against the walls. He was a mess. He couldn't breathe. Sherlock's eyes flew open and he leapt off the couch, grabbing his Belstaff before heading out the door.

* * *

He heard her before he saw her. From his hiding spot in a dark corner of the Bart's locker room, Sherlock could detect the familiar sound of her sensible flats pattering down the tiled hallway. He didn't immediately reveal himself when he heard the click of the handle and the soft squeak of the hinges as the door opened. No, he stayed in his corner, ignoring the pang of desire deep in his gut when his eyes landed on her. One hand rested in the pocket of her white lab coat was the other was pressing into the muscles of her shoulder. Her back was hunched slightly; her long day of bending over corpses was evident. Her eyes downcast, she moved straight to her locker, quickly fiddling with the lock before pulling it open. The mirror that she kept on the inside for those days when she had a date right after work caught Sherlock's reflection. It took Molly a few moments to notice. With a soft gasp she whirled around, her eyes locking on his. The corners of Sherlock's mouth turned up in a soft smile as he read her face.

He'd expected her to be overjoyed at his return, to run into his arms and bury her face in his chest…but she didn't move. Instead a look of relief and dread crossed her face before a small smile formed on her lips.

"Sherlock," she exhaled. His eyes trailed her figure. She looked…different. Her eyes were tired but still possessed the same light they had when he went away. Sherlock could detect a fifteen pound weight gain since his departure but she was still quite small. Her breasts were noticeably larger and her hips fairly wider, both characteristics associated with…

"Mummy!" a familiar voice rang out through the locker room before a mop of brown curls ran into the room and straight to Molly. Sherlock tried and failed to force air down his lungs.

Molly plastered on a smile and picked up the boy, spinning him before turning her gaze to Sherlock, the dread he'd noticed before settled into her eyes. She turned to the woman that had followed the boy in. "Thanks Catherine. He'll see you tomorrow. Say thank you to Miss Catherine, sweetheart."

"Thank you Catherine," the boy said waving. Molly turned her attention back to Sherlock.

"Now Scott, this is—"

"Sherlock!" the boy shouted excitedly. Molly looked at the boy completely baffled.

"Scott…Scott, darling, how do you know Sherlock?"

"He's my friend," Scott explained. Molly's eyes flew to Sherlock for confirmation. He nodded.

"He's your...he's your friend? How...I'm sorry...how did you two meet?"

"We met at the park this morning."

"He's quite perceptive for a three year old. Saw through my disguise in seconds," Sherlock forced out, his tongue dry in his mouth. Scott nodded enthusiastically.

Molly could feel the room spinning as her eyes searched Sherlock's face for _something_. The consulting detective's eyes were fixated on her face as he attempting in vain to control his breathing.

"Oh, well then. Sherlock there's…there's something we need to talk about," Molly whispered. Sherlock felt his heart rate elevate. He glanced at his watch.

"Forgive me, Molly. It seems I am late for a meeting with my brother. Scott, it was good to see you again," Sherlock offered with a small smile. Scott grinned. "And Molly, I believe belated congratulations are in order."

"Sherlock I really need to…" Molly started, but Sherlock was already moving to the door. "Sherlock, it's really—" The sound of the door closing cut her off.

"I like him," Scott whispered to his mother after a moment of silence.

"I do too, buddy," Molly said before kissing Scott's hair. "Let's go home."


End file.
